LCP water barrier film and method of making same

Abstract

The application relates to the technical field of polymer films, and particularly discloses an LCP water-blocking film and a preparation method thereof. The LCP water-blocking film comprises an LCP bottom layer and a graphene layer, the LCP bottom layer and the graphene layer are connected through a bonding layer, raw materials of the bonding layer comprise the following components in parts by weight: polyurethane acrylate oligomer 50-70 parts, monomer 40-60 parts, photoinitiator 2-6 parts, polyvinylidene fluoride 5-10 parts and solvent A 20-30 parts; and raw materials of the LCP bottom layer comprise the following components in parts by weight: liquid crystal polymer 70-90 parts, solvent B 60-70 parts, modified filler 10-15 parts, cellulose 3-5 parts and plasticizer 5-10 parts.

Description

Technical Field

[0001] This application relates to the technical field of polymer thin films, and in particular to an LCP water-blocking thin film and its preparation method. Background Technology

[0002] Liquid crystal polymers (LCPs) are a novel type of polymer material that, under certain physical conditions, exhibits both the fluidity of a liquid and the physical properties of a crystal, as well as anisotropy. LCPs possess high mechanical properties, good dimensional stability, chemical resistance, and low dielectric constant and dielectric loss at high frequencies, making them widely applicable. In recent years, with the rapid development of the electronics industry and the widespread application of 5G technology, electronic devices are becoming increasingly miniaturized and feature-rich. The requirements for packaging substrates in high-tech fields such as communications, industrial automation, and aerospace are becoming increasingly stringent. LCP films, with their low dielectric constant, low dielectric loss, and extremely low coefficient of linear expansion under high-frequency conditions, are flourishing in high-frequency, high-speed copper-clad laminate applications. While LCP films possess some water-blocking properties due to their low hygroscopicity, this limits their application in areas with even higher water-blocking requirements. Summary of the Invention

[0003] To improve the water-blocking performance of LCP films, this application provides an LCP water-blocking film and its preparation method.

[0004] Firstly, this application provides an LCP water-blocking film, which adopts the following technical solution:

[0005] An LCP water-blocking film includes an LCP substrate and a graphene layer, wherein the LCP substrate and the graphene layer are connected by an adhesive layer; the adhesive layer comprises the following components in parts by weight: 50-70 parts of polyurethane acrylate oligomer, 40-60 parts of monomer, 2-6 parts of photoinitiator, 5-10 parts of polyvinylidene fluoride, and 20-30 parts of solvent A; the LCP substrate comprises the following components in parts by weight: 70-90 parts of liquid crystal polymer, 60-70 parts of solvent B, 10-15 parts of modified filler, 3-5 parts of cellulose, and 5-10 parts of plasticizer.

[0006] By adopting the above technical solution, the cellulose in the LCP bottom layer rapidly expands into a gel when it encounters water, which can effectively prevent water from entering. The modified filler can fill some gaps, thus giving the LCP bottom layer good water-blocking performance. The graphene layer has good water-blocking performance, so it is composited onto the LCP bottom layer using an adhesive layer, which improves the performance of the final composite film. The polyvinylidene fluoride in the adhesive layer can also give the adhesive layer a certain water-blocking performance, thus further improving the water-blocking performance of the obtained LCP water-blocking film.

[0007] In one specific implementation, the method for preparing the modified filler includes the following steps:

[0008] γ-aminopropyltriethoxysilane, ethanol, and water were stirred and mixed evenly to obtain the modified solution;

[0009] Nano-activated carbon and nano-graphene are stirred and mixed evenly to obtain a mixture. During the stirring process, the modification liquid is sprayed onto the mixture. After spraying, stirring is continued and the mixture is dried to obtain the modified filler.

[0010] By adopting the above technical solution, γ-aminopropyltriethoxysilane is dissolved in ethanol, then sprayed onto nano-activated carbon and nano-graphene, and dried. This allows γ-aminopropyltriethoxysilane to modify nano-activated carbon and nano-graphene, improving their dispersion performance. Nano-graphene has strong hydrophobic properties, while nano-activated carbon can adsorb water vapor. Therefore, by combining the two, the water-blocking performance of the LCP bottom layer can be improved.

[0011] In one specific implementation, the weight ratio of the modified liquid to the mixture is 1:(13-14).

[0012] By adopting the above technical solution, the ratio of the modified liquid to the mixture is further limited, which allows γ-aminopropyltriethoxysilane to better modify nano-activated carbon and nano-graphene, thereby improving the performance of the modified filler.

[0013] In one specific embodiment, the monomer comprises a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate.

[0014] By adopting the above technical solution, the bonding strength of the adhesive layer can be improved by using a composite monomer composed of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate.

[0015] In one specific implementation, the photoinitiator comprises a mixture of 2,4,6-trimethylbenzoyldiphenoxyphosphine and 1-hydroxycyclohexylphenyl ketone.

[0016] By adopting the above technical solution and using a composite photoinitiator composed of 2,4,6-trimethylbenzoyldiphenoxyphosphine and 1-hydroxycyclohexylphenyl ketone, the adhesive layer can be better formed.

[0017] In one specific implementation, solvent A comprises N,N-dimethylformamide.

[0018] In one specific implementation, solvent B comprises polyethylene glycol.

[0019] In one specific implementation, the cellulose comprises a mixture of methylcellulose and hydroxyethylcellulose.

[0020] By adopting the above technical solutions, methylcellulose has good water-blocking properties, hydroxyethylcellulose has good thickening effect, and it is also beneficial to the formation of membrane.

[0021] In one specific embodiment, the plasticizer includes one or more of dimethyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate, di-2-octyl phthalate, diethyl phthalate, dibutyl phthalate, and diisononyl phthalate.

[0022] Secondly, this application provides a method for preparing an LCP water-blocking film, which adopts the following technical solution:

[0023] A method for preparing an LCP water-blocking film includes the following steps:

[0024] LCP underlayer preparation: Liquid crystal polymer, modified filler and cellulose are added to solvent B and stirred at 55-65℃ for 2-3h. Then, plasticizer is added at room temperature and stirring is continued for 1-2h to obtain LCP raw material. Finally, LCP raw material is melt-extruded and blown into film to obtain LCP underlayer.

[0025] Adhesive preparation: First, polyvinylidene fluoride is dissolved in solvent A to obtain a polyvinylidene fluoride solution. Polyurethane acrylate oligomer, monomer, and photoinitiator are stirred and mixed evenly. Then, the polyvinylidene fluoride solution is added, stirred, and diluted with ethyl acetate to obtain the adhesive.

[0026] Composite: The graphene layer is a graphene film. The graphene film and the LCP bottom layer are composited using an adhesive, followed by UV curing. The adhesive forms an adhesive layer between the graphene layer and the LCP bottom layer, resulting in an LCP water-blocking film.

[0027] By adopting the above technical solution, liquid crystal polymer, modified filler, and cellulose are first added to solvent B, heated and stirred, then plasticizer is added, and then melt extrusion blown film is performed to obtain LCP bottom layer; then polyurethane acrylate oligomer, monomer, and photoinitiator are stirred, polyvinylidene fluoride solution is added, stirred and diluted with ethyl acetate to obtain binder, and finally the binder is used to composite LCP bottom layer and graphene film to obtain LCP water-blocking film with good water-blocking performance.

[0028] In summary, this application includes at least one of the following beneficial technical effects:

[0029] 1. In this application, the cellulose in the LCP substrate rapidly swells into a gel when it comes into contact with water, which can effectively prevent water from entering. The modified filler can fill some gaps, thus giving the LCP substrate good water-blocking properties. The graphene layer also has good water-blocking properties, so it is composited onto the LCP substrate using an adhesive layer, which improves the performance of the final composite film. The polyvinylidene fluoride in the adhesive layer can also give the adhesive layer a certain water-blocking property, thus further improving the water-blocking properties of the obtained LCP water-blocking film.

[0030] 2. In this application, γ-aminopropyltriethoxysilane is dissolved in ethanol, then sprayed onto nano-activated carbon and nano-graphene, and dried. This allows γ-aminopropyltriethoxysilane to modify the nano-activated carbon and nano-graphene, improving their dispersion performance. Nano-graphene has strong hydrophobic properties, while nano-activated carbon can adsorb water vapor. Therefore, by combining the two, the water-blocking performance of the LCP bottom layer can be improved.

[0031] 3. The method in this application first adds liquid crystal polymer, modified filler, and cellulose to solvent B, heats and stirs, then adds plasticizer, and then melts and extrudes the film to obtain an LCP underlayer; then stirs polyurethane acrylate oligomer, monomer, and photoinitiator, adds polyvinylidene fluoride solution, stirs and then dilutes with ethyl acetate to obtain an adhesive, and finally uses the adhesive to composite the LCP underlayer and graphene film to obtain an LCP water-blocking film with good water-blocking performance. Detailed Implementation

[0032] The present application will be further described in detail below with reference to the embodiments.

[0033] All raw materials used in the examples are commercially available. The polyurethane acrylate oligomer was provided by Shanghai Yinchang New Materials Co., Ltd., product number YC3100; the liquid crystal polymer was provided by Suzhou Xinsuyu Plastic Raw Materials Co., Ltd., model number E7008; the graphene film was provided by Nanjing Jicang Nanomaterials Co., Ltd.; the plasticizer includes, but is not limited to, one or more of dimethyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate, di-2-octyl phthalate, diethyl phthalate, dibutyl phthalate, and diisononyl phthalate, with dimethyl phthalate being preferred in this application.

[0034] Preparation Example

[0035] Preparation Example 1

[0036] Preparation Example 1 provides a method for preparing a modified filler, comprising the following steps:

[0037] γ-aminopropyltriethoxysilane, ethanol, and water were stirred and mixed evenly to obtain a modified solution; wherein the weight ratio of γ-aminopropyltriethoxysilane, ethanol, and water was 5:18:2.

[0038] Nano-activated carbon and nano-graphene were stirred and mixed evenly to obtain a mixture. During the stirring process, the modification liquid was slowly sprayed onto the mixture. After spraying, stirring was continued for 0.5 hours, and then dried at 105℃ for 1 hour to obtain the modified filler. The weight ratio of nano-activated carbon to nano-graphene in the mixture was 1:1, and the weight ratio of modification liquid to mixture was 1:12.5.

[0039] Preparation Example 2

[0040] The difference between Preparation Example 2 and Preparation Example 1 is that the weight ratio of the modified liquid to the mixture is 1:13; the remaining steps are the same as those in Preparation Example 1.

[0041] Preparation Example 3

[0042] The difference between Preparation Example 3 and Preparation Example 1 is that the weight ratio of the modified liquid to the mixture is 1:13.5; the remaining steps are the same as those in Preparation Example 1.

[0043] Preparation Example 4

[0044] The difference between Preparation Example 4 and Preparation Example 1 is that the weight ratio of the modified liquid to the mixture is 1:14; the remaining steps are the same as those in Preparation Example 1.

[0045] Preparation Example 5

[0046] The difference between Preparation Example 5 and Preparation Example 1 is that the weight ratio of the modified liquid to the mixture is 1:14.5; the remaining steps are the same as those in Preparation Example 1.

[0047] Preparation Example 6

[0048] The difference between Preparation Example 6 and Preparation Example 3 is that the nano-activated carbon was stirred, and during the stirring process, the modification liquid was slowly sprayed onto the nano-activated carbon. After the spraying was completed, the stirring was continued for 0.5 h, and then dried at 105 °C for 1 h to obtain the modified filler. The weight ratio of the modification liquid to the nano-activated carbon was 1:13.5. The remaining steps were the same as those in Preparation Example 3.

[0049] Preparation Example 7

[0050] The difference between Preparation Example 7 and Preparation Example 3 is that the nano-graphene was stirred, and during the stirring process, the modification liquid was slowly sprayed onto the nano-graphene. After the spraying was completed, the stirring was continued for 0.5 h, and then dried at 105 °C for 1 h to obtain the modified filler. The weight ratio of the modification liquid to the nano-graphene was 1:13.5. The remaining steps were the same as those in Preparation Example 3. Example

[0051] Example 1

[0052] Example 1 provides a method for preparing an LCP water-blocking film, comprising the following steps:

[0053] LCP underlayer preparation: 70 kg of liquid crystal polymer, 10 kg of the modified filler from Preparation Example 1, and 3 kg of cellulose were added to 60 kg of solvent B and stirred at 60 °C for 2.5 h. Then, 5 kg of plasticizer was added at room temperature and stirring was continued for 1.5 h to obtain LCP raw material. Finally, the LCP raw material was melt-extruded and blown into a film to obtain an LCP underlayer with a thickness of 20 micrometers. The cellulose included a mixture of methylcellulose and hydroxyethylcellulose, and the weight ratio of methylcellulose to hydroxyethylcellulose was 1:1. The plasticizer was dimethyl phthalate. Solvent B was polyethylene glycol.

[0054] Adhesive preparation: First, 5 kg of polyvinylidene fluoride (PVDF) was dissolved in 20 kg of solvent A to obtain a PVDF solution. Then, 50 kg of polyurethane acrylate oligomer, 40 kg of monomer, and 2 kg of photoinitiator were stirred and mixed evenly at 25 °C. Finally, the PVDF solution was added, stirred, and diluted with ethyl acetate to obtain the adhesive, such that the weight fraction of ethyl acetate in the adhesive was 40%. Solvent A was N,N-dimethylformamide; the monomer was a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate, with a weight ratio of 1:1; the photoinitiator was a mixture of 2,4,6-trimethylbenzoyldiphenyloxyphosphine and 1-hydroxycyclohexyl phenylone, with a weight ratio of 1:1.

[0055] Composite: The graphene layer is a graphene film. First, the adhesive is applied to the LCP bottom layer with a thickness of 8 micrometers. Then, the graphene film is laminated on top. Next, it is placed in a 532nm UV curing machine for 30 seconds to cure. The adhesive forms an adhesive layer between the graphene layer and the LCP bottom layer, resulting in an LCP water-blocking film.

[0056] Example 2

[0057] The difference between Example 2 and Example 1 is that the modified filler used in Example 2 is selected; the remaining steps are the same as in Example 1.

[0058] Example 3

[0059] The difference between Example 3 and Example 1 is that the modified filler used in Example 3 is selected; the remaining steps are the same as in Example 1.

[0060] Example 4

[0061] The difference between Example 4 and Example 1 is that the modified filler used in Example 4 is selected; the remaining steps are the same as in Example 1.

[0062] Example 5

[0063] The difference between Example 5 and Example 1 is that the modified filler used in Example 5 is selected; the remaining steps are the same as in Example 1.

[0064] Example 6

[0065] The difference between Example 6 and Example 1 is that the modified filler used in Example 6 is selected; the remaining steps are the same as in Example 1.

[0066] Example 7

[0067] The difference between Example 7 and Example 1 is that the modified filler used in Example 7 is selected; the remaining steps are the same as in Example 1.

[0068] Example 8

[0069] Example 8 provides a method for preparing an LCP water-blocking film, comprising the following steps:

[0070] LCP underlayer preparation: 80 kg of liquid crystal polymer, 12.5 kg of modified filler from Preparation Example 3, and 4 kg of cellulose were added to 65 kg of solvent B and stirred at 60 °C for 2.5 h. Then, 7.5 kg of plasticizer was added at room temperature and stirring was continued for 1.5 h to obtain LCP raw material. Finally, the LCP raw material was melt-extruded and blown into a film to obtain an LCP underlayer with a thickness of 20 micrometers. The cellulose included a mixture of methylcellulose and hydroxyethylcellulose, and the weight ratio of methylcellulose to hydroxyethylcellulose was 1:1. The plasticizer was dimethyl phthalate, and solvent B was polyethylene glycol.

[0071] Adhesive preparation: First, 7.5 kg of polyvinylidene fluoride (PVDF) was dissolved in 25 kg of solvent A to obtain a PVDF solution. Then, 60 kg of polyurethane acrylate oligomer, 50 kg of monomer, and 4 kg of photoinitiator were stirred and mixed evenly at 25 °C. Finally, the PVDF solution was added, stirred, and diluted with ethyl acetate to obtain the adhesive, such that the weight fraction of ethyl acetate in the adhesive was 40%. Solvent A was N,N-dimethylformamide; the monomer was a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate, with a weight ratio of 1:1; the photoinitiator was a mixture of 2,4,6-trimethylbenzoyldiphenyloxyphosphine and 1-hydroxycyclohexyl phenylone, with a weight ratio of 1:1.

[0072] Composite: The graphene layer is a graphene film. First, the adhesive is applied to the LCP bottom layer with a thickness of 8 micrometers. Then, the graphene film is laminated on top. Next, it is placed in a 532nm UV curing machine for 30 seconds to cure. The adhesive forms an adhesive layer between the graphene layer and the LCP bottom layer, resulting in an LCP water-blocking film.

[0073] Example 9

[0074] Example 9 provides a method for preparing an LCP water-blocking film, comprising the following steps:

[0075] LCP underlayer preparation: 90 kg of liquid crystal polymer, 15 kg of modified filler from Preparation Example 3, and 5 kg of cellulose were added to 70 kg of solvent B and stirred at 60 °C for 2.5 h. Then, 10 kg of plasticizer was added at room temperature and stirring was continued for 1.5 h to obtain LCP raw material. Finally, the LCP raw material was melt-extruded and blown into a film to obtain an LCP underlayer with a thickness of 20 micrometers. The cellulose included a mixture of methylcellulose and hydroxyethylcellulose, and the weight ratio of methylcellulose to hydroxyethylcellulose was 1:1. The plasticizer was dimethyl phthalate, and solvent B was polyethylene glycol.

[0076] Adhesive preparation: First, 10 kg of polyvinylidene fluoride (PVDF) was dissolved in 30 kg of solvent A to obtain a PVDF solution. Then, 70 kg of polyurethane acrylate oligomer, 60 kg of monomer, and 6 kg of photoinitiator were stirred and mixed evenly at 25 °C. Finally, the PVDF solution was added, stirred, and diluted with ethyl acetate to obtain the adhesive, such that the weight fraction of ethyl acetate in the adhesive was 40%. Solvent A was N,N-dimethylformamide; the monomer was a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate, with a weight ratio of 1:1; the photoinitiator was a mixture of 2,4,6-trimethylbenzoyldiphenyloxyphosphine and 1-hydroxycyclohexyl phenylone, with a weight ratio of 1:1.

[0077] Composite: The graphene layer is a graphene film. First, the adhesive is applied to the LCP bottom layer with a thickness of 8 micrometers. Then, the graphene film is laminated on top. Next, it is placed in a 532nm UV curing machine for 30 seconds to cure. The adhesive forms an adhesive layer between the graphene layer and the LCP bottom layer, resulting in an LCP water-blocking film.

[0078] Example 10

[0079] The difference between Example 10 and Example 8 is that the cellulose is methylcellulose; the remaining steps are the same as in Example 8.

[0080] Example 11

[0081] The difference between Example 11 and Example 8 is that the cellulose is hydroxyethyl cellulose; the remaining steps are the same as in Example 8.

[0082] Example 12

[0083] The difference between Example 12 and Example 8 is that the monomer is 3-(2-furanyl)-2-acrylic acid; the remaining steps are the same as in Example 8.

[0084] Example 13

[0085] The difference between Example 13 and Example 8 is that the monomer is isooctyl acrylate; the remaining steps are the same as in Example 8.

[0086] Example 14

[0087] The difference between Example 14 and Example 8 is that the photoinitiator is 2,4,6-trimethylbenzoyldiphenyloxyphosphine; the remaining steps are the same as in Example 8.

[0088] Example 15

[0089] The difference between Example 15 and Example 8 is that the photoinitiator is 1-hydroxycyclohexylphenyl ketone; the remaining steps are the same as in Example 8. Comparative Example

[0090] Comparative Example 1

[0091] Comparative Example 1 provides a method for preparing an LCP water-blocking film, comprising the following steps:

[0092] 70 kg of liquid crystal polymer, 10 kg of the modified filler from Preparation Example 1, and 3 kg of cellulose were added to 60 kg of solvent B and stirred at 60 °C for 2.5 h. Then, 5 kg of plasticizer was added at room temperature and stirring was continued for 1.5 h to obtain LCP raw material. Finally, the LCP raw material was melt-extruded and blown to obtain LCP water-blocking film with a thickness of 20 micrometers.

[0093] Comparative Example 2

[0094] Comparative Example 2 provides a method for preparing an LCP water-blocking film, comprising the following steps:

[0095] 80 kg of liquid crystal polymer and 3 kg of cellulose were added to 60 kg of solvent B and stirred at 60 °C for 2.5 h. Then, 5 kg of plasticizer was added at room temperature and stirring was continued for 1.5 h to obtain LCP raw material. Finally, the LCP raw material was melt-extruded and blown to obtain LCP water-blocking film with a thickness of 20 micrometers.

[0096] Performance testing experiment

[0097] Water barrier performance: The films in each embodiment and comparative example were tested using a water vapor transmission rate tester. The test conditions were 38°C and 90% relative humidity. Each sample was measured 4 times and the average value was taken to obtain the water vapor transmission rate. The lower the water vapor transmission rate, the better the water barrier performance of the film.

[0098] Table 1 Performance test results of the thin film

[0099] Combining Example 1 and Comparative Examples 1-2, the film in Example 1 exhibits the best water-blocking performance. This demonstrates that in the film of this application, the cellulose in the LCP bottom layer swells into a gel when exposed to water, effectively preventing water from entering. The modified filler can fill some gaps, thus giving the LCP bottom layer good water-blocking performance. Furthermore, a graphene layer is laminated onto the adhesive layer. The graphene layer itself has good water-blocking performance, and the polyvinylidene fluoride in the adhesive layer can give the adhesive layer a certain degree of water-blocking performance, thereby improving the water-blocking performance of the final LCP water-blocking film.

[0100] In conjunction with Examples 1-5, the films in Examples 2-4 exhibit better water-blocking properties. This indicates that when preparing the modified filler, the preferred ratio of the modified liquid to the mixture is 1:(13-14). The better the modification effect of the modified filler, the better the water-blocking performance of the final LCP water-blocking film.

[0101] Combining Examples 3, 6, and 7, the film in Example 3 exhibits the best water-blocking performance. This indicates that when preparing the modified filler, the filler is preferably a composite filler composed of nano-activated carbon and nano-graphene. Nano-graphene has strong hydrophobic properties, while nano-activated carbon can adsorb water vapor. Therefore, by combining the two, the LCP bottom layer exhibits good water-blocking performance.

[0102] Combining Examples 3, 8, and 9, the film in Example 8 exhibits the best water-blocking performance. This indicates that when preparing the LCP underlayer and binder, increasing the amount of raw materials used results in the water-blocking performance of the LCP water-blocking film first increasing and then decreasing.

[0103] Combining Examples 8, 10, and 11, the film in Example 8 exhibits the best water-blocking performance. This indicates that when preparing the LCP substrate, the preferred cellulose is a mixture of methylcellulose and hydroxyethylcellulose, which results in a LCP substrate with good water-blocking performance.

[0104] Combining Examples 8, 12, and 13, the film in Example 8 exhibits the best water-blocking performance. This indicates that when preparing the adhesive, the monomer is preferably a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate, which results in a better adhesive performance and can further improve the water-blocking performance of the LCP underlayer.

[0105] Combining Examples 8, 14, and 15, the film in Example 8 exhibits the best water-blocking performance. This indicates that when preparing the adhesive, the photoinitiator is preferably a mixture of 2,4,6-trimethylbenzoyldiphenoxyphosphine and 1-hydroxycyclohexylbenzophenone. During UV curing, this improves the bonding strength between the LCP substrate and the graphene layer, thereby further enhancing the water-blocking performance of the prepared LCP substrate.

[0106] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. An LCP water-blocking film, characterized in that: The material comprises an LCP substrate and a graphene layer, which are connected by an adhesive layer. The adhesive layer comprises the following components by weight: 50-70 parts of polyurethane acrylate oligomer, 40-60 parts of monomer, 2-6 parts of photoinitiator, 5-10 parts of polyvinylidene fluoride, and 20-30 parts of solvent A. The LCP substrate comprises the following components by weight: 70-90 parts of liquid crystal polymer, 60-70 parts of solvent B, 10-15 parts of modified filler, 3-5 parts of cellulose, and 5-10 parts of plasticizer. The monomer comprises a mixture of 3-(2-furanyl)-2-acrylic acid and isooctyl acrylate.

2. The LCP water-blocking film according to claim 1, characterized in that: The method for preparing the modified filler includes the following steps: γ-aminopropyltriethoxysilane, ethanol, and water were stirred and mixed evenly to obtain the modified solution; Nano-activated carbon and nano-graphene are stirred and mixed evenly to obtain a mixture. During the stirring process, the modification liquid is sprayed onto the mixture. After spraying, stirring is continued and the mixture is dried to obtain the modified filler.

3. The LCP water-blocking film according to claim 2, characterized in that: The weight ratio of the modified liquid to the mixture is 1:(13-14).

4. The LCP water-blocking film according to claim 1, characterized in that: The photoinitiator comprises a mixture of 2,4,6-trimethylbenzoyldiphenoxyphosphine and 1-hydroxycyclohexylphenyl ketone.

5. The LCP water-blocking film according to claim 1, characterized in that: Solvent A includes N,N-dimethylformamide.

6. The LCP water-blocking film according to claim 1, characterized in that: Solvent B includes polyethylene glycol.

7. The LCP water-blocking film according to claim 1, characterized in that: The cellulose comprises a mixture of methylcellulose and hydroxyethylcellulose.

8. The LCP water-blocking film according to claim 1, characterized in that: The plasticizer includes one or more of dimethyl phthalate, butyl benzyl phthalate, dicyclohexyl phthalate, di-2-octyl phthalate, diethyl phthalate, dibutyl phthalate, and diisononyl phthalate.

9. A method for preparing an LCP water-blocking film as described in any one of claims 1-8, characterized in that: Includes the following steps: LCP underlayer preparation: Liquid crystal polymer, modified filler and cellulose are added to solvent B and stirred at 55-65℃ for 2-3h. Then, plasticizer is added at room temperature and stirring is continued for 1-2h to obtain LCP raw material. Finally, LCP raw material is melt-extruded and blown into film to obtain LCP underlayer. Adhesive preparation: First, polyvinylidene fluoride is dissolved in solvent A to obtain a polyvinylidene fluoride solution. Polyurethane acrylate oligomer, monomer, and photoinitiator are stirred and mixed evenly. Then, the polyvinylidene fluoride solution is added, stirred, and diluted with ethyl acetate to obtain the adhesive. Composite: The graphene layer is a graphene film. The graphene film and the LCP bottom layer are composited using an adhesive, followed by UV curing. The adhesive forms an adhesive layer between the graphene layer and the LCP bottom layer, resulting in an LCP water-blocking film.

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